Automated preference testing apparatus for rating palatability of foods

An electronic preference testing apparatus is described for measuring taste preference of rodents and other small animals with solid or liquid foods. The apparatus is designed on the principle of the two-choice, preference technique. It operates photoelectrically with a sequence of presentations so that whenever a subject eats from a compartmentalized food tray, a standard and a test food are each briefly sampled alone before both foods are presented together (in alternate positions) for preference determination. Preferences are automatically recorded on digital counters. The apparatus is built in two modules (a preference tester and the master control) connected by multiconductor cable. The modular design provides portability and isolation of the animals from the major noise-producing components. Diagrams of the apparatus are given, and test results from a trial that evaluated positional bias and a sucrose-concentration preference experiment are presented to demonstrate its application in research.